US2566631A

US2566631A - Clutch control mechanism

Info

Publication number: US2566631A
Application number: US773837A
Authority: US
Inventors: Earl R Price
Original assignee: Bendix Aviation Corp
Current assignee: Bendix Aviation Corp
Priority date: 1947-09-13
Filing date: 1947-09-13
Publication date: 1951-09-04
Anticipated expiration: 1968-09-04

Description

p 1951 E. R. PRICE 2,566,631

' CLUTCH CONTROL MECHANISM 3 Sheets-Sheet 1 Filed Sept. 13, 1947 a A /I w [I [Z y 2/ w 40 /Z 3 M Z5 [3 I 6 1 INVENTORS fABL E. Heme A Tmewzy 4, 1951 E. R. PRI CE 2,566,631

CLUTCH CONTROL MECHANISM Filed Spt. 15, 1947 s Shetg-Sheet 2 I 4 64 E4421. 3 met A TTOEA/E Y Sept. 4, 1951 E. R. PRICE CLUTCH CONTROL MECHANISM Filed Sept. 13. 194'? 3 Sheets-Sheet 5 ATTORNEY Patented Sept. 4, 1951 I UNITED STATE PATENT oFr 2,566,631 ICE 2 ,566,631 GLI I IGH CONTROL MECHANISM Earl Price, South Bend,-Ind., assignor ,to BendiX A 'at ion coi'poratioli'f sontli' a corfloraftionof Delaware Application September 13, 19.47, ,SerialNo. 773,837

5 claim 1 This invention relates in general to power means .for operating the friction clutch of an automotive vehicle and in particular to pressure differential operated power means controlled -by an operation of the accelerator of the vehicle and by anoperation vof the engine of the vehicle.

One of the principal objects of my invention .is to provide a clutch control mechanism including a pressure differential operated motor controlled by valvemechanism includin a threerway pressure balanced follow-upvalve which is op rative in accordance with the position of the accelerator and the speedof thevengine.

Another object of .my invention is to provide, in the power plantof an automotive vehicle in,-

-cluding a friction clutch, a change speed transmission and an accelerator, a vacuum operated clutch control mechanism comprising a single acting motor, said motor being controlled by a :pressurebalanced three-way yalve which is actufited, through the intermediary of a floating lever, by the accelerator and .a-pressure differ,-

ential and spring operated ,motor, the operation o e t r bein con olledby mea i di n in f eret ewa e zpi mp- Yet another object of my invention is to pro.- vid power mean fo rep atin th frie e clutch of an automotive vehicle said power means serving to effect two stages of clutch engaging movement of the driven elementof the clutch as it moves into engagement with theldrivin'g element of the clutch said two stage operation of .the clutch driven element being effected by "a throttle opening movernent of the accelerator and by engine speed c ontrolled means.

A further object of my invention is to provide,

in an automotive power plant including a friction clutch and a change speed transmission, a clutch control mechanism including a motor and valve means for controlling the op'eratioi'i of. said motor,

said valvemeans comprisingan accelerator and engine controlled three-way valveand a cut ofi valve, the latter valve serving to disable the operation of the former valve when the transmission is established in its high gear setting.

Yet another object of my invention is to provide, in the power plant of an automotive vehicle including a friction clutch, an accelerator and a three speeds forward and reverse transmission,

power means for operating the clutch including a pressure differential operated motor operatively connected to the clutch, valve means for controlling the operation of eaid motor including a three-way valve controlled vby a vehicle speed responsive governor, the accelerator and the change speed transmission, andfurther including another three-way valve controlled by the accelerator and a plurality .of pressure difierential operated motors; said power means being operative to disengage the clutch by the release of the accelerator when the transmission is established in any gear except high gear andalso ,,operative to disengage the clutch, when the ransmissi n i establ sh d hi r a by an operation of the g ernor and the accelerator.

ete wther bie ef an n, eiii m vide a clutch control mechanism adaptedlto be used in th rv ow rrlents ai qmb r w e -seamen A 7 pla e rel es e. etie p T v 10 meshe te 2 9 e l the 9 has w n r e re e ne e rsesie a eb e hie t i The above and 0th r tee invention will appear in norm eon'sid t take da m' 'swh -t .e b to erm -rrra egerr prete ,af r n maeiv w o r m m principal features"a'f'my'inveneam' Figure -2 ,is a planyiew loo kingat eneend of t me valvemechanism ,ofimyinventionf N d ina'l'seo'tionalview talgen ,igifi:

solenoid ope ted jvallv e mechanism} re ex-'5 eg' new,deemin err ec re -e t of the '.connee tion in conn 'cti igftli aceelefator, thethrottle andt control valverand 'Figure ,6"is a I d closing' a portidnof the v emel aei e es mo fi dl r vid enbther e rpeme ra a wr e v l m hiiol'aei m o m l hr i e D-eseribing' now'that embodiment of my in 3 motion connection between the pedal 20 and crank l6 makes possible a power operation of the clutch without moving the clutch pedal.

One end of the motor [0, that is, the end of the same constituting a part of the aforementioned power compartment 13 of the motor, is connected by a conduit 22 to a compartment 24 of a control numeral 26 and three different views of said unit are disclosed in Figures 2 to 4 inclusive. The casing 26 of the unit 26 is provided with a cylindrically shaped bore to receive a cylindrical sleeve valve member -28-constituting one of the two parts of a three-way valve; and said casing is counterbored to provide the aforementioned compartment 24, Figure '3.

"A valve member 30, which is biased inwardly by a spring 3! andwhich is provided with a 03- lindricallyshaped bore to permit the passage of air therethrough, constitutes the other part of the two part three-way valve. One end of the latter valve member, is provided with diametrically spaced openings to receive therethrough a pin 32 and said pin extends-through a connecting pin'34, one end of which extends within the member 30. The other end of the pin 34 extends beyond the valve member 30 and is detachably and pivotally'connected to a two-part lever 36; The end portion 38 of the pin 34 is preferably biased into engagement with the interior of the valve 30 by a-coil spring 40. There is thus provided means for readily disconnecting valve 30 from the lever 36; for the pin 32 may be removed by driving the same through the pin :4; thereby separating the latter from the valve As is disclosed'in Figure 3; the lever 36 is pivotally connected at one of its ends to a rod 4|; and the movement of the rod to the left, Figure 3, is limited by-a stop 42-adjustably mounted in the valve casing. The other end of the lever 35 'is pivotally connected to a pin 43 which is slidably received at one of its ends in a portion of the valve casing and which is secured at its other end to a flexible diaphragm 44. This diaphragm constitutes the power element of a valve operating pressure differential operated motor indicated as a whole by the reference numeral 45; and the operation of said motor is in large measure controlled by the gaseous pressure within the control compartment 46 of said motor, and by a compression spring 41 within said compartment. A compartment 48 of the motor 45 is vented to the atmosphere via a conduit 49 which leads to an air cleaner 50, Figure 2.

The most important feature of jm'y invention lies in the provision of a fluid pressure operated motor 23 which cooperates with the motor 45 and the accelerator H8 in the control of the valve 30. This motor 23 includes a two part casing 25 and a power element 21, one of the casing parts receiving a conduit 23 which is preferably connected to the high pressure side of a water pump 33 constituting a part of the cooling system of the internal combustion engine 62 of .the vehicle.

is ported to receive a conduit 35 which may be connected to the low pressure side of the pump system. The power element 21 of the motor 23 is connected to the power element of the motor 45 by a rod 31.

The'other part of the motor casing driven by said engine. I ow the power element 21 is connected to the valve operating diaphragm 44, accordingly it is apparent that the loadin valve unit indicated as a whole by the reference Describing the operation of the motor 23 the of said diaphragm is in part controlled by the loading of the power element 2'1; and this feature of my invention will be brought out in the description to follow.

Continuing the description of the valve mechanism 26, the valve member 30 is recessed at 5| and the end of said member provides a land portion 52 which is adapted, in the operation of the valve, to be positioned to register the recess 5| with ports 53in the valve member 28. The member 30 is also operated so that. the land portion 52 covers the ports 53, that is, laps the valve; and said member isalso operated to interconnect said ports with theair cleaner 50 via the compartment 48 and the interior of the valve.

The valve member 28 is provided with an opening 53 to register with one end of a duct 54 in the valve casing, said duct registering at its other end with a chamber 55 of a three-way vacuum cutin valve indicated as a whole by the reference numeral 56 and disclosed in detail in Fig.- ure 4. The latter valve includes a valve member 51 secured to one end of an armature 58 of a solenoid 59. When the solenoid 59 is energized the valve member 57 moves downwardly, Figure l, to seat at 66, thereby connecting the duct 54 with the intake manifold 6| of theinternal combustion engine 62 of the vehicle via a conduit 53 and the aforementioned chamber 55; and when the solenoid 59 is de-energized, a spring 64 serves to move the armature upwardly, Figure 4, to seat the valve member 5? at 65, thereby cutting off the vacuum connection and venting the duct 54 to the atmosphere via the air cleaner 50, chamber 48of the motor 45, a recess 65 in the valve casing which houses the outer end of the pin 43, a duct 66 in the valve casing, and the chamber 55. A spring loadedcheck valve 61 may be included in the vacuum connection between the intake manifold and the valve chamber 55 thereby providing a means for maintaining the clutch disengaged in the event the conduit 53 is broken when the motor 16 is energized.

Completing the description of the valve unit 26 the casing'26' is provided with a duct 32, Figure 3, permanently interconnecting the control'compartment 46 of the motor 45 with the aforementioned valve compartment 24. There is thus provided fluid transmitting means for atall times interconnecting the motor compartment 45, the valve compartment '24, and the control compartment l3 of the clutch operating motor i0. It follows therefore that the operation of the clutch control mechanism constituting my inventionis controlled by controllingthe gaseous pressure within the valve compartment 24.

There is thus provided a compact valve control unit 26 comprising a multi-s'ectioned casing housing a three-

way control valve

28,36 and means for operating said valve comprising the fluid pressure motor 23, a spring and pressure differential operated motor 45 and an accelerator operated pin 4!, said pin 'and'the power element 44 of the motor being connected with the movable part 36 of said valve by means of a floating lever member 36. f 'f Describing now the force transmitting means interconnecting the accelerator H6 of the car with a throttle operating crank I20 and with the valve operating pin 4!, said pin is connected to r a rod 88 and this rod is pivotally connected with alev'er member'3ilf'The lowerend of this lever 5 member is pivotally mounted upon a fioating pin 1'22 "andone end of this pin is mounted in one end of a bell crank lever i24 which is pivotally mounted upon "a fiixed-pin I262. The lever member 99' is connected to the accelerator 158 by 'in'eansof a rod I28, a bell crank lever I39 and a link "[32 all as disclosedin Figure 1; and as disclosed in the latter figure, the bell crank lever 12 4 isconnecte'd to the throttle valve'of the carburetor "by means of a link ltd, a crank 535, a rod 138, a crank l lii, a link i l? and the crank 120. A spring I'M, which is weaker than a throttle return spring H55, is operative, tog-ether with the spring M5, to return the accelerator 'to its throttle closed position andfto move the valve member as to the right, Figure 3, to open the three=way valve 28, 3Q, that'is, operate the same to effect 'a'clutch disengaging operation of the motor Ill. The spring i lfl is preferably sleeved over the pin 22 and connected at its ends to the levers '93 and iE 'i. The operation of this part'oi the mechanism of my invention will be described in greater detail hereinafter when the operation of the entire clutch control mechanism is f described in detail.

Describing now an important feature of my iiiv'en'tion, the solenoid "58 which operates the vacuum cutin valve 55, is controlled 'by'the electrical controls disclosed in Figure l. Describing this'mechanism a'g'rouiided battery is is wired in series with an ignition switch 58, a clutch control 'cutout switches preferably mounted inthe instrumntpaneloi the vehicle, the solenoid 59, "a'rida grounded switch "H which is opened by the second and high gear shift rail of the transmission ?2 when the transmission is established in its high gear setting. With this electrical "hoolgupthe 'va1ve5S is opened, that is, the valve member 5'! is seated at Bi when the switches -68 and B9 are closed "and the transmission is established in any gear except high gear; accordingly, with the vacuum cutin valve opened there 'isprovid'ed a souroe'of vacuum to make possiblea clutch disengaging operation 'of the motor iii when the accelerator is released to open the'valve 38 an operation which is. de-

scribed in detail "hereinafter.

With the vehicle'traveling in high gear it is 'desirable to'automatically disengage the clutch when the accelerator is'released. andthespeed of the'v'ehicleis appreciably reduced, for example when the vehicle is being driven very slowly 'in traffic or in a'fuiieral procession;and to effect this operation of the inechanism'oi my invention there is provided a switch '53 which is 'clos e dwhen the accelerator is released to close the throttle, andagroundedswitch i l-which is operated by a vehicle speed responsive governor, @not shown. To effect the operation of the'switch 3 there isprovided a flange '35 on the rod I28, said flange being contaetablewith a switch operated member it. I

As is disclosed in Figure 1 the switches Hand 13 areelectrically connected'in series in an electrical circuitwhichis wired in parallel with the -grounded transmission operated switch 7 l. 'Prei- --erably the switch i3 is so constructed and so -operated--by-theflange lfi that the same is closed just prior to the complete closing of the throttle valve; and'it follows, therefore, that the switch '13 isnotopened until-after the throttle has been *opened to a limited degree.

, 'Theabove described clutch control mechanism :of my invention maybe incorporated in the power plant of a vehicle'which includes a-kickdown' type of selective gear transmission, that is, a transmission which may, by -manual operation of 9. shift lever, be established in one 'orlthe o'ther of two forward "gear settings and a-r'eve'rse gear setti-'ng; and aiteron'e of said'for 'w'ard 'gear-settings is established then a pressure differential and spring operated -kickdown motor unit, con'trolled by 'a vehicle speed responsive governor and the -acee1emtor of the vehicle, takes over the operation of said transmission. In this type :of well "Known transmission mechanism the kickdo'wn or sownsma operation 0f the inotor unit is facilitated by a momentary disabling of the ignition system of the engine; and the power plant ineluding such a mechanism -rnay als'o-include' a "fluid-coupling.

Describing now the complete operation of the mechanism constituting 'my invention and incidentally completing the description of the parts thereof not heretofore described, when the accelerator l I 8 is completely released to -idl'e -th'e-internal combustion engine 5 i4 and move the lever 90 to the position disclosed in Figure '5, the in- -takemanifold i l2 of said engine is partially-evacuated. There is thus provided a source of vacuu'mior-energizingthe motor [0 to disengage'the friction clutch of the motor vehicle; and this operation is effected inasmuch as with the release of the accelerator the movable three-way valve member 30 is moved to place said motor in air transmitting connection with the manifold. The valve member 3ii and the means for operating the same then assume the'relative positions disclosed in Figure 3, the spring 4'! being compressed by the joint operation of the power elements 27 and 44 both of which are at the time subjected to differentials of pressure developed by the idling e'ngine. Air is then withdrawn from the clutch motor and the motor compartment into the intake manifold via theconduit'63, the valve compartment 55, the duct interconnecting the compartment 55 with the port 53, Figure'3, recess 5|, ports 53, the compartment 24, the duct 92 interconnecting the compartment 24 with the "valve motor compartment 46, and the conduit 22 interconnecting the compartment 24 with the control chamber of the clutch motor Ill.

The compartment 45 being then partially evacuated the diaphragm 44 is moved, by the differential ofpressures acting on the same, to the position disclosed in Figure 3; for the gaseous pressure within the compartment 46 is at this time the same'as that within" the intake manifold of the idling engine and this gaseous pressure is of course the same as that Within the control compartment of the then energized clutch operating motor I0; and as described above the engine ,idling position of the diaphragm 44 is at this time controlled in part by the operation of the power element '21. It is to be noted that in the "clutch disengaged position of the parts the valve member 30 is moved'to the position disclosed in Figure" 3, that is, a position justshort of a closing oiT of the ports 53 by the flanged endo'f said valve member, that is, the land 52.

Now it is to be noted that the air transmitting connection with the intake manifold is made possible by virtue of the fact that thevalvemem- *beriii of the vacuum cutin valve unit 56 is at 'the time removed from a seat for thesolenoid 59 which actuates said valve member is at the time energizedto move the armature 58 and-the valve member 57 connected thereto downwardly, Figure '4. Explaining this operation the solenoid 59-is at-this timeenergized-byvirtue of a closing 'of the grounded breaker switch 14; for inasmuch as the car is at a standstill the vehicle speed responsive governor, not shown, is then operative to close said switch. The governor is so constructed that when the vehicle is at a standstill or is traveling below a relatively low speed, say ten miles per hour, then the governor is operative to close the grounded switch 14 thus completing an electrical circuit including the switch I4, the then closed accelerator operated switch 13, the solenoid 59, the cutout switch 69, the ignition switch 63 of the vehicle and the grounded battery I0.

Continuing now the description of the cycle of clutch control operations of the motor I 0, said. motor having been energized to disengage the" clutch the driver will then probably wish to establish the change speed transmission of the vehide in a relatively low gear setting. This is, of course, done by moving the transmission controlling selector lever, not shown, to its low gear position."

Continuing now the description of the cycle of operations of the clutch control mechanism, the

power plant of the vehicle is now prepared to,-

efiect a forward movement of the vehicle accordingly the driver depresses the accelerator to open .the throttle and effect a clutch engaging operation of the clutch operating power means. De-

scribing the latter operation with the first incre- .ment of movement of the accelerator the lever 90 is rotated counterclockwise about the pin I22 as a fulcrum, this operation being made possible by virtue of the fact that the spring I44 is weaker than the throttle spring 145 and the latter,

spring is strong enough to prevent the rotation of the lever I 24. In this operation the lever 99 moves counterclockwise until a flange 204 at the upper end of the same contacts an adjustable stop 206 on the lever I24; and this movement of the lever 90 results in a movement of the rod 88 to the left, Figure 3, to rotate the lever member about its pivotal connection with the pin 43 as a fulcrum. The valve member Bil is thus moved to the left, Figure 3, the lever 36 operating as a lever of the second class to place the valve ports 53 in communication with a valve chamber 2E0 which chamber is at all times connected to the atmosphere via the interior of the valve member 30 and the valve compartment 43 which is vented to theatmosphere via the air cleaner 7 50. It is to be noted that in this initial operation of the valve the degree of movement of the valve member 30 is greater, preferably about twice as great, as the degree of movement of the rod I28 connected to the accelerator. As will be brought out in the description that follows there is thus provided a valve operating mechanism operative to quickly efiect the first stage operation of the motor I0 during the'first increment of depression of the accelerator, said increment being 'relatively small. It is to be remembered that there is neither an opening of the throttle nor an opening of the switch I3 during this 'movement of the accelerator.

The valve member 30 having been moved to the left to vent the valve compartment 24 to atmosphere there results a relatively rapid flow of air into both the control compartment I3 of the clutch operating motor I0 and the compartment 46 of the valve operating motor and this flow of air results in a clutch engaging operation of the motor III. Describing this operation the power element of the motor I0 is moved to the right, Figure 1, by the clutch springs and with each other, the movement of the power element is arrested.

Explaining this arresting operation the clutch springs, by their expansion, serve to maintain a relatively low gaseous pressure, that is vacuum, within the control chamber I3 of the motor I 0. Now inasmuch as said control chamber is'at all times connected to the valve chamber 24 and motor chamber 46 it follows that the gaseous pressure within said chambers is also maintained relatively low by virtue of the expansion of the clutch springs. As described above, when the clutch springs have expanded a certain amount, that is, when their vacuum creating power has decreased to a certain factor, then the spring 4'! expands to the right, Figure 3, thereby lapping the three-way valve 28, 30. Describing this operation of said valve the valve member 39 moves to the right until the ports 53 register with the land portion 52 of said valve member; and when this occurs the flow of air into the chamber 46 and the motor It] is automatically cut oif an the system is then in equilibrium. In this operation the lever 99 rotates counterclockwise about the pivot-al connection between the pin I22 and said lever, said pivotal connection acting as a fulcrum. As stated above, the parts of the mechanism of my invention are so constructed and arranged, particularly the strength or load of the clutch springs, the area of the diaphrams 21 and 44 and the weight of the spring 47, that the valve is lapped to arrest the movement of the power element of the clutch motor when the clutch plates are just short of contact with each other. j

This operation of the motor I0 is usually described as the first stage operation thereof and it is to be particularly noted that by varying the weight of the spring 41 or by varying the area of the piston 21, that the termination of the first stage operation of the motor may be varied. in other words, by varying the weight of the spring 41' there is provided means for varying the degree of separation of the clutch plates when the first stage of clutch engaging operation of the motor I0 is completed. It is to be noted the mechanism of my invention is preferably so constructed that this first stage of clutch engaging operation of said motor is completed before or at substantially the same time as the opening of the throttle is initiated and as a result of a relatively small degree of depression of the accelerator. This first stage operation of the motor i0 is completed very quickly and with a. normal operation of the accelerator the driver may momentarily arrest the depression thereof when the resistance of the throttle return spring I45 is encountered; and this momentary arresting of the depression of the accelerator will suffice to insure a completion of the aforementioned first stage of clutch engaging operation of said motor before the throttle is opened.

To effect the step by step second stage of clutch engaging operation of the motor- I0 the driver continues the depression of the accelerator thereby efiecting a clockwise rotation of the bell crank lever I24 to open the throttle; and. this operation of the accelerator serves to again effect a leftward movement of the rod 88. and a leftward movement of the valve member 30 the lever 36 again fulcruming about it pivotal'connection with the pin 43. This operation, as with the above described first stage clutch engaging operation of the motor, serves to again place the clutch motor compartment 46 and the control greener compartment: of: the clutch motor It in commu-- member again moves. to its'lapped' position by virtue of av resumption. of the expansion of the spring 41.. In this valve lapping: operation the direction of movement of the; valve member 30 is again reversed; the: lever. 36 fulcrumin about its connection with the pin 4!. above described first stage of: clutch engaging operation of the mechanism the spring 4.! expands to move the valve member so to itslapped position whenthe differential of pressure acting on the diaphragm 44, offset by the differential; of pressure acting upon the: power element 21,. is reduced to a certain factor by the flow of air into the chamber 48; As with the first stage operation of the mechanism, the valve is lapped. when the summation of forces biasing the pin 43 to the left equals that biasing said pin to the right.

The clutch plates are thus first moved just short of engagement with each other and then pressed into contact, said latter operation being effected by a succession of steps if the driver chooses to depress the accelerator by a succession of steps; and hewill probably do thi if he desires to effect a slipping operation of the.

clutch. The latter operation is, of course, necessary in effecting a very slow movement of the car such as when parking the same. The first stage operation of the mechanism, that is, the operation to effect the relatively rapid movement of the clutch plates up to a point just short of engagement with each other, will, by virtue of'the relatively fast movement of the valve member 39' and. its degree of movement during the initial increment of: movement of the accelerator, be effected very quickly. The second stage clutch. engaging. operation of my i clutch control mechanism is effected. more slowly inasmuch as the bell: crank'lever I24- is operated as'a throttle operating lever of: the first class, the levers 90 and I24 moving as a. unit about the: pin 1'26; and by virtue of this operation. the degree of clutch engaging movement of; the valve member 30 is relatively small compared to: the degree of movement of: the accelerator to effect said movement. It is also to be remembered that the first stage of clutch engagingoperation of the clutch is, with a normal operation of. the

accelerator, completed before or at substantially the same time as the opening'movement of the throttle is initiated. The adjustable stop 42" serves to control the mechanism to. limit the clutch plate loading factor said factor preferably being such as to prevent a stalling of the engine.

The. clutch being engaged and the accelerator partially depressed the driver then further depresses the accelerator to speed up the vehicle with the transmission established in low gear; and when the desired vehicle speed is attained the driver will then release the accelerator preparatory to establishing the transmission in a higher gear ratio setting.

There is thus provided, by the friction clutch control mechanism of my invention, power means for effecting the disengagement of the clutch: when. the accelerator is'released' to idle A with the 10'v the engine and the transmission is established in any one of its low, reverse, or second gear settings; or when. the accelerator is released to idle the engine, the vehicle is traveling below governor speed or is at rest, and the transmission-is'establishedin its high gear setting. In the latter clutchz disengaging operation of the power means the accelerator, in its operation of:

the. three-way valve' 2'8, 3'0; cooperates with the governor in its operation of closing the switch 1'4" and the: accelerator H8 inits operation of closing the switch 13-, the latter operation being effected: when the "throttle" is slightly opened" thereby' providing means for. driving the vehicle in high gear; at a relatively low" vehicle speed As to the clutch engaging operation of the power means of my invention, said: operation is ef= fect ed,- through the intermediary of the floating! lever 3%; by an operation of the accelerator and" an operation of: the vaive operating motors 45 and.- 23: It is' alsoto'be noted that with the" clutch control mechanism of my invention if the" driver should fail to depress the accelerator to" operate the valve 28, 30 just after the transmission is established in its-high gear setting, that" the bleed of air into the motor In via the duct 66 will nevertheless insure an engagement of the clutch. This operation of 'th'e: mechanism might be effected if the transmission were placed in its" high-gear setting just before the vehicle started" to descend-agrade;

The: valve mechanism of myinvention which is the mostimportant feature thereof, insures-atwo stage operation of the clutch motor and. a resulting smooth engagement-of theclutch, with anymode of operatiorrot the accelerator; for

the operation ofthe leverage changing force" transmitting connections and the throttle spring; 145 virtually insure-this-two stage operation ofthe mechanism. when the clutch is engaged as aresult of" anormal operation. of the accelerator. The floating lever 36- interconnecting therecip rocable valve member 30. with the accelerator operated pin 4| and the power elements of the valve. operating motors 2:3 and 45,- provide a very simple, yet effective, means for operating the three-way control valve: 28, 30'; the. varying of the weight of. the spring 41. provides'a means for determining when the. first stage of: engagement of the. clutch. is. completed; the particular force transmitting means interconnecting the throttle valve, thevalve member 30 and the accelerator H8 insures a completion. of the. first stagev of engagement of the clutch just as the throttle. is. opened or is about tobe opened; the step'by step clutchv engaging or disengaging operations 01? the power element Of the. clutch. motor insures the desired. maneuvering oi the vehicle-in traffic. or when. the. vehicle. is being parked; and the. operation of the motor 23- provides a means:- cooperating-withthe. accelerator to effect a con currentengine torquecontrolling means and. accelerator position controlling meansior deter-- mining the clutch plate loading operation. of the clutch motor i0: It is. desirable to load; the clutch platesin accordance with the position or. the accelerator pedal; and it isalsodesirable to make. said loading a function of the engine torque; With.- the clutch control mechanism ofmy invention the clutch plate loading is a function of both of the aforementioned factors;

There is disclosed in Figure 6 a modified form of valve controlling motor; and the parts of.- saidmotor which duplicate like parts in themotor 2-3 of, Figureiii, are given-the samereierence numeral with the addition of a prime. The motor of clusion of a spring 13' housed within a compartment l of the motor; and by the provision of a lost motion connection between a power element 21 and a rod 3'! the latter being slidable through the power element. A flange l 9 is fixedly mounted on the rod 31' and said flange is adapted to abut the power element 21' when said element is moved to the left as described below.

Describing the operation of the motor 23 of Figure 6 the parts of themechanism are shown in their positions when the engine is idling} The spring I 3' then serves to move the power element 21" to the right to separate the flange [9 from said element. With a normal clutch engaging operation of the mechanism of my invention the pin 31' will move to the right in the valve lapping operation; and this movement will not be obstructed by the power element 21. However, should the driver inadvertently or by design suddenly open the throttle to accelerate the vehicle and thereby appreciably accelerate the speed ofthe engine,

then it .would be desirable to delay the lapping of'the valve until the clutch plates were appreciably loaded, that is, loaded sufiiciently to efiect the desired acceleration of the vehicle; and with the control mechanism of Figure 6 this result will be accomplished inasmuch as with the aforementioned speeding up of the engine there results sufficient fluid pressure upon the power element 27' to overcome, that is compress, the spring l3 thereby moving the power element to the left. The power element 21' by this oper-- ation springs into action as a yieldable stop to resist the movement of the pin 31' to the right thereby delaying the lapping operation of the valve; and this delay results in the admission of a greater quantity of air into the control chamber [3 of the clutch motor thereby efiecting a more substantial loading of the clutch plates.

There'is thus provided, by the motor 23, means for automatically increasing the clutch' plate loading operation of the mechanism should the speed of the engine be increased to or above a certain criticalfactor.

Although only two embodiments of the invention have been illustrated and described, various changes in the form and relative arrangements of the parts may be made to suit requirements.

I claim:

1. Clutch control mechanism adapted to be included in the power plant of an automotive vehicle, said mechanism including a fluid pressure motor, valve means for controllin the operation of said motor including a pressure balanced valve member and means for actuating said member including force transmittin means adapted to be connected to the accelerator of the vehicle and further'including a fluid pressure motor operable in accordance with the pressure fluid therein, together with another fluid pressure motor operable in accordance with the speed of the engine of the vehicle.

2. Mechanism for operating the friction clutch of an engine driven vehicle comprising a fluid pressure motor, valve means for controlling the operation of said motor including'a pressure balanced reciprocable valve member, and means for controlling the operation of said valve member including manually operable means for moving said valve member, a spring and pressure differential operated motor for moving said valve member, and a fluid pressure operated motor operable in accordance with engine speed and operative to "control the operation of said pressur difierential operated motor.

3. Mechanism for operating the friction clutch of an engine driven vehicle comprising a fluid pressure motor, valve means for controlling the operation of said motor including a pressure balanced reciprocable valve member, and means for controlling the operation of said valve member including a lever member pivotally connected to the valve member, manually operable means connected to one end of said lever member and operable, through the intermediary of the lever. member, to move said valve-member, a pressure differential operated motor for moving said valve member, said motor also being connected to the lever membenand a spring and fluid pressure operated motor operable in accordance with engine speed and operative to control the operation of said pressure diiferential operated motor.

4. Mechanism for operating the friction clutch. of an engine driven vehicle comprising a fluid pressure motor operably connected to the driven element of the clutch, valve means for controlling the operation of said motor including a reciprocable pressure balanced valve member, a lever member pivotally connected to one end of said:

valve member, manually operable means pivotal- 1y connected to one end of the lever member, a.

when and only when the power element of the water pressure operated motor is subjected to a hydrostatic force equal to or exceeding a certain factor.

5. Mechanism for operating the friction clutch of an engine driven vehicle comprising a fluid pressure motor operably connected to the driven element of the clutch, valve means for controlling the operation of said motor including a reciprocable pressure balanced valve member, a

lever member pivotally connected to one end of said Valve member, manually operable means pivotally connected to one end of the lever member, a spring and pressure difierential operated motor including a power element operably connected to the other end of the lever member, a water pressure operated motor including a power element operably connected to the power element of the last mentioned motor, and a spring within the water pressure operated motor, said spring serving to render the motor operable as a control means when and only when the power element thereof is subjected to a force equal t or exceeding a certain factor.

EARL R. PRICE.

REFERENCES CITED The following references'are of record in the file of this patent:

UNITED STATES PATENTS